LED test / review - Unknown 5050 SMD LED similar to XM-L2 - extremely surprising results, even better than the original?!

LED test

Unknown 5050 SMD LED similar to Cree XM-L2

A few weeks ago I ordered a Revtronic F30B (formerly known as 'Nitefighter' F30B) flashlight. My intention was to use this light as host and remove the driver and LED.

As I would expect, there was not an original XM-L2 inside, but a 'counterfeit' model.

Because of this (also after long search manufacturer and part no. are unknown to me) there's no datasheet or other informations. It's also unknown to me where you can get this LED.

The LED chip was made in classic lateral design, the two bonding wires including the solder pads are visible. There is a similarity to the known Cree XM-L2, also the substrate color and the arrangement of dots on the yellow phosphor layer are almost the same. Because (not only) of this I think that the manufacturer used a Cree EZ1950-p LED chip (datasheet here, pdf) which can purchased from Cree directly.

Around the LED chip itself yellow stains are visible. Under the chip a sort of thermal- or solder paste was squeezed out in production process and is visible in top view. The outer size is 4.985 x 4.985 mm (0.196 x 0.196 in, known as '5050 size') and it fits on a XM board easily as well.

On the picture the left corner of the grey substrate is broken. I'm not sure that was caused by the production or the assembly process of the flashlight.

Here the comparison with a genuine Cree XM-L2 LED (left).

The light emitting surface (LES) of this emitter is only 7.75 mm² (0,0120 sq in) in size. This is also smaller than of the XP-L and XM-L2 (approx. 8.6 mm²). In the second picture of the die you can see that the highest luminance on the chip surface is reached near the bonding wires. In the next time I will standardize these pictures to get a real comparison option between different LEDs.

25 °C Tsp, unless noted otherwise.


  • maximum current: 8,400 mA (2,289.3 lm @ 4.09 V) - at 8,500 mA death of LED
  • power at maximum 34.4 W
  • efficiency at maximum 66.5 lm/W
  • sweet spot at 5,800 mA (1,917.4 lm @ 3.57 V)
  • power at sweet spot 20.7 W
  • efficiency at sweet spot 92.6 lm/W

I define the sweet spot as the position in the diagram which gives a good average between light flux, current and efficiency. In most cases it lays roughly 15 to 35 percent lower than maximum possible light flux.

This LED delivers an very surprising high amount of light flux! It is almost as good as the Cree XP-L in bin V5, and can handle much higher current than the (newer version) XM-L2 U2. Also the Vf is much lower than of the other LEDs! At 8,500 mA the bonding wires are blown, the same limiting factor known from XM-L2 and many other LEDs. I recommend a maximum current of 7,400 - 7,800 mA and not more than 3.8 - 3.9 V to stay on the safe side.

The performance behavior is almost the same as of the original XP-L V5 and XM-L2 T5/T6. This supports my guess that the unknown manufacturer uses an original Cree EZ1950-p chip to produce the light in the LED.

Because of the smaller LES the luminance at the same light flux will be higher as of the XM-L2! Especially in dedomed state this LED could break some luminance values known from XM-L2 and Luminus SST40-W. Unfortunately I cannot test this anymore because this LED was the only I had. Overall I am very interested to get the official manufacturer and supplier of this LED.

The tint was very nice. It was a clear white at approx 6000 K CCT, without any green or yellow color in it. But I had to say that this is valid only for my LED; in other cases the tint might be completely different. Maybe one of you know the true manufacturer/type of this LED or could name a supplier of it - it would be an interesting LED to build thrower with the XM footprint.

Thanks for reading!

Greetings, koef3

Mistakes and suggestions are best sent via pm.

This sort of reminds me when the clones of the IBM PC came out. At first they weren’t as good. Then COMPAQ came out with a 100% compatible portable, beating even IBM……………………….
Maybe some day?..…………

That’s some nice efficacy.
Maybe we can ask Revtronic about the manufacturer? Or at least get them to sell the emitter alone…

Mitko mentioned this Led in a thread , some months ago… I can’t find the post but i’m pretty sure it’s the same one. Visible dots on the phosphor and good performance :+1:

Maybe, that's all what I found (Flare Light Enterprise Ltd.). But I'm not sure that they give us the datasheet (which is needed to work with that LED properly).

By the way it is possible to buy the LED chips from Cree. In this case it might be possible that the unknown manufacturer used a EZ1950-p chip which was soldered by them on their own substrate.

Nice work koef3. :+1:

Thanks for the test. Let’s now wait for chinese leds to clearly beat the established manufacturers :slight_smile:

I contacted Revtronic for further informations on this LED and if it maybe possible to buy some bare emitter.
Maybe it is possible to get a datasheet or the manufacturer’s name.

Now I’m sure that the manufacturer used an original Cree EZ1950-p LED chip with their own phosphor layer, the arrangement of the dots and also the performance behavior is exactly the same compared to the XM-L2.

Could this be a new manufacturing process xm-l2? All my old revtronic lights seem to be real cree as far as I can tell. Was your board glued in too? If so, how did you remove it? I haven’t managed to get mines out.

Could you make sharp and close pictures from the LED so we can prove this? Personally i am not sure about this and also I not believe this was a production process change of the XM-L2. For this I would rather expect that the die size would be bigger.
My board wasn’t glued in the head. I could just pry it out easily. The white stuff under the board is not glue but thermal paste.

I took some cell phone pics, unfortunately I don’t have a better camera. Pics are of various xml-2 laying around and two of xml-2 mounted in revtronic lights. I have 2 F30b with glued in mcpcb from amazon US. The F20 is also from amazon US and the MT20 from banggood and they are not glued in. As far as I know, I have never gotten a fake xml-2 of the 30 or so I have. They all have the same die, bond wires, bond wire pads, etc. All but two perform about the same in eyeball test. Old xml is the opposite, I only have 3 real xml out of 50 or so.
Group image Left Column 1. Crelant 7G5CS 2. Revtronic F20B 3. Thorfire VG10 4. Thorfire VG10 Right Column 1. unkown, sofirn maybe? 2. unkown, sofirn maybe? 3. odepro kl42 4. sofirn aimai ac33 5. another unkown off to the side I moved to copper board
Revtronic F30b
Revtronic MT20

In thinking about this more, the led you pictured has sloppy phosphor application, which is characteristic of fake crees xp-g2 I have. Hot dedoming for those results in blue led. Performance of those are also very close to real xp-g2 in eyeball test.

When did you buy the F30B? Are there any serial numbers on the battery tube or head?

On the pictures, for me the XM-L2 seems to be genuine. Interesting: my F30B (bought at Banggood begin December 2017, where this unknown 5050 LED came from) has another LED board version.

It is made out of aluminium, but it hasn't DTP.

PS: One week ago I asked for the type of LED. Revtronic has not answered yet.

I got mines from Amazon US in January of 2017. There are no serial numbers on mine.

I don’t think you will get a response from them, as no brand wants to admit to using fakes.

Possibly, and looks like the clone of the XM-L2, (Latticebright XM2 , > http://www.latticebright.com/En/cpzs1/2017-01/16/NewsView-370.html
) discussion on the influx of clones forma couple years ago is here: - The Fake-Cree LED Awareness Thread - The new "low" in Budget lights.

The big problem is (also in this forum) that nearly every non-Cree (but very similar to Cree) LED is called ‘LatticeBright’ which makes an exact determination of the real type impossible. ‘LatticeBright’ is used as a kind of categpry to name these.
Not all counterfeit LEDs out there are Lattucebright. In this special case it can’t be a LatticeBright XM2 because I tested this type already. More than 5 Amps are not possible with it.

the xm2 datasheet i have shows the wirebonds almost at the die corners.
so not likely using a cree die.